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Sparklyr using case_when with variables


Sparklyr fails when using a case_when with external variables.

Working Example:

test <- copy_to(sc, tibble(column = c(1,2,3,4)))
test %>%
  mutate(group = case_when(
                   column %in% c(1,2) ~ 'group 1',
                   column %in% c(3,4) ~ 'group 2'))

Fails with Error: Can't extract an environment from NULL

test <- copy_to(sc, tibble(column = c(1,2,3,4)))
group1_cols <- c(1,2)
group2_cols <- c(3,4)
test %>%
  mutate(group = case_when(
                   column %in% group1_cols ~ 'group 1',
                   column %in% group2_cols ~ 'group 2'))

Solution

  • Try unquoting the variables:

    test %>%
      mutate(group = case_when(
        column %in% !!group1_cols ~ 'group 1',
        column %in% !!group2_cols ~ 'group 2'))
    

    For more info check out the dplyr programming vignette http://dplyr.tidyverse.org/articles/programming.html